单项选择题A.Because nearly 1,000 million acres of land was burned off.B.Because natural resources are being used up.C.Because animals and plants arc in danger of extinction.D.Because natural beauty of the land would be ruined.
单项选择题A.He couldn’t see the steamer clearly.B.He failed to attract the attention of the steamer.C.The steamer refused to help him.D.The cliff was too steep for him to climb.